AME, Inc. Low Power DC/DC Boost Converter AME5131 n General Description The AME5131 is a high-frequency boost converter dedicated for LCD bias supply and white LED applications for cellular phone backlighting, PDAs, and other hand-held devices. The part can also be used to generate standard 3.3 V/5 V to 12 V power conversions. The AME5131 has an internal 400mA switch current limit, offering lower output voltage ripple. The 32µA low quiescent current together with an optimized control scheme, allows device operation at high efficiencies and maintains long battery lifetime. AME5131 uses SOT-25 package and gives a small size solution. n Function Block Diagram On / Off Time Controller UVP SW VIN _ Boost Controller + FB Bandgap Driver + _ GND Enable Soft Start EN n Features l 0.6Ω Internal Switch n Typical Application l 1.8V to 5.5V Input Range l Adjustable Output Voltage Up to 28V l Input Under Voltage Protection l 32µA Typical No Load Quiescent Current 5 V IN l SOT-25 Package Standards D1 VOUT VIN ~28 V 1.8 V-5.5 V l 1µA Shutdown Current l All AME's Lead Free Products Meet RoHS L1 10μH VIN SW AME5131 CIN 4.7μF FB 4 EN GND 1 R1 2.1M CFF 22PF CO 1μF 3 2 R2 150K n Applications l White LED Back-Lighting l Hand-held Devices l Digital Cameras l Portable Applications l Internet Audio Player l LCD Bias Power l Standard 3.3 V/5 V to 12 V Conversions 1 AME, Inc. Low Power DC/DC Boost Converter AME5131 n Pin Configuration SOT-25 Top View 5 AME5131AEEV 4 1. SW 2. GND AME5131 3. FB 4. EN 1 2 5. VIN 3 * Die Attach: Conductive Epoxy n Pin Description Pin Number 2 Pin Name Pin Description 1 SW This is the switch pin and is connected to the drain of the internal NMOS power switch. Minimize the metal trace area connected to this pin to minimize EMI. 2 GND Ground Pin. 3 FB Feedback Input Pin. Connect this pin to the external voltage divider to program the desired output voltage. 4 EN Enable Control Input Pin. (Active High) 5 VIN Input Supply Pin. Place bypass capacitor as close to VIN as possible. AME, Inc. Low Power DC/DC Boost Converter AME5131 n Ordering Information AME5131 x x x x xxx x Special Feature Output Voltage Number of Pins Package Type Operating Ambient Temperature Range Pin Configuration Pin Configuration A (SOT-25) Operating Ambient Package Type Temperature Range Number of Pins Output Voltage E: -40OC to +85OC V: 5 ADJ: Adjustable 1. SW 2. GND 3. FB 4. EN 5. VIN E: SOT-2X Special Feature Z: Lead free n Ordering Information Part Number Marking* Output Voltage Package Operating Ambient Temperture Range AME5131AEEVADJZ BEFww ADJ SOT-25 -40OC to +85OC Note: ww represents the date code and pls refer to Date Code Rule page on Package Dimension. * A line on top of the first letter represents lead free plating such as BEFww. Please consult AME sales office or authorized Rep./Distributor for the availability of package type. 3 AME, Inc. Low Power DC/DC Boost Converter AME5131 n Absolute Maximum Ratings Parameter Symbol Maximum VIN 6 VEN , VFB VIN VSW 30 Input Supply Voltage EN, FB Voltages SW Voltage Unit V C* ESD Classification Caution: Stree above the listed absolute maximum rating may cause permanent damage to the device. HBM C: 4000V+ n Recommended Operating Conditions Parameter Symbol Rating Ambient Temperature Range TA -40 to +85 Junction Temperature Range TJ -40 to +125 Unit O C n Thermal Information Parameter Package Die Attach Thermal Resistance* (Junction to Case) Thermal Resistance (Junction to Ambient) SOT-25 Conductive Epoxy Internal Power Dissipation Maximum Unit θJC 81 o C/W θJA 260 o C/W PD 400 mW Maximum Junction Temperature 150 o C Solder Iron (10 Sec)** 350 o C * Measure θJC on center of molding compound if IC has no tab. ** MIL-STD-202G210F 4 Symbol AME, Inc. Low Power DC/DC Boost Converter AME5131 n Electrical Specifications VIN = 2.4V, EN = VIN, TA = -40oC to 85oC, typical values are at TA = 25oC Parameter Input Voltage Symbol Test Condition VIN Min Typ 1.8 Max Units 5.5 V Quiescent Current IQ IOUT = 0mA, not switching, VFB = 1.3V 32 50 Shutdown Current ISD EN = GND 0.1 1 FB Pin Bias Current IFB VFB = 1.3V Feedback Trip Point VFB 1.8V ≦ VIN ≦ 5.5V UVP Voltage UVP µA 1 1.187 1.212 1.237 V 1.5 1.7 V 400 450 mA ICL VOUT = 18V, IOUT = 10mA, TA=25oC RDSON VIN = 2.4V; ISW = 200mA 0.6 1 Ω SW leakage current ISW VSW = 28V 1 10 µA Switch Off Time t OFF 400 ns Switch On Time t ON 6 µs EN Input Current IEN EN = GND or VIN EN Input Threshold (High) VEH Device Active EN Input Threshold (Low) VEL Device Shutdown Switch Current Limit Switch RDSON Line Regulation REGLINE Load Regulation REGLOAD 1.8≦VIN ≦5.5V; VOUT =18V; ILOAD =10mA; Cff = not connected VIN =2.4V; VOUT =18V; 0mA≦IOUT≦30mA 350 0.1 1 1.3 µA V 0.4 V 0.3 %/V 0.15 %/mA 5 AME, Inc. AME5131 n Detailed Description Operation The AME5131 is a boost converter with a smart control scheme that operates in a pulse frequency modulation (PFM) with constant peak current control. The smart control schemes utilize a reference voltage, minimum off-time, maximum on-time and current-limited control scheme. The switch turns off as the inductor current reaches the internally set peak current of 400mA (typical). The second criteria that turns off the switch is the maximum on-time of 6µs (typical). As the switch is turned off the external Schottky diode is forward biased delivering the current to the output. The switch remains off for a minimum of 400 ns (typical), or until the feedback voltage drops below the reference voltage. Using this PFM peak current control scheme the converter operates in discontinuous conduction mode (DCM) where the switching frequency depends on the output current, which results in high efficiency over the entire load current range. This regulation scheme is inherently stable, allowing a wider selection range for the inductor and output capacitor. Soft-start Soft-start is provided on the AME5131 to minimize inrush current. All inductive boost converters exhibit high inrush current during start-up if no special precaution is made. This can cause voltage drops at the input rail during start up and may result in an unwanted or early system shut down. The soft-start time is set by increasing the current limit in two steps starting from 100mA for 256 cycles to 200mA for the next 256 cycles, and then full current limit. 6 Low Power DC/DC Boost Converter AME, Inc. Low Power DC/DC Boost Converter AME5131 Efficiency vs Output Current Efficiency vs Input Voltage 90 100 Io=5mA 90 80 VIN =5.0V Io=10mA 70 V IN =3.6V 70 Efficiency (%) Efficiency(%) 80 V IN =2.4V 60 50 40 30 50 40 30 20 20 10 10 0 60 0 1 0 1.8 100 10 2 2.5 3 3.5 4 4.5 Output Current (mA) Input Voltage (V) VOUT vs IOUT VOUT vs VIN 19 5 5.5 6 20 18 I OUT=10mA 17 V IN =2.4V 19 VO UT (V) VOUT (V) 16 15 14 18 13 17 12 11 10 0.1 1 10 16 1.8 100 IOUT (mA) 2 2.5 3 3.5 4 4.5 5 5.5 6 VIN (V) Quiescent Current vs Input Voltage Feedback Voltage vs Temperature 1.240 60 TA =85 C 50 40 Feedback Voltage (V) Quiescent Current (µA) 1.235 o TA =25oC 30 TA =-40oC 20 1.230 1.225 1.220 1.215 1.210 1.205 1.200 1.195 1.190 1.185 10 1.2 1.8 2.4 3 3.6 4.2 4.8 Input Voltage (V) 5.4 6 6.6 1.180 -40 -20 0 20 40 60 80 100 120 Temperature (oC) 7 AME, Inc. Low Power DC/DC Boost Converter AME5131 RDSON vs Temperture RDSON vs Input Voltage 1000 1200 900 800 700 800 RDSON (mΩ) RDSON (mΩ) 1000 600 400 600 500 400 300 200 200 100 0 -20 -10 0 10 20 30 40 50 o 60 70 80 90 0 1.8 2.4 3 3.6 4.2 4.8 Temperature ( C) Input Voltage (V) Load Transient Response Line Transient Response VIN 5.4 6 3.4V 2.4V VOUT 100mV/div VOUT 100mV/div 10mA IOUT 1mA 200µS/div 200µS/div Start Up Behavior 5V/div 1V/div VOUT 50mA/div EN I IN Time 8 AME, Inc. Low Power DC/DC Boost Converter AME5131 n Date Code Rule Marking Date Code Year A A A W W xxx0 A A A W W xxx1 A A A W W xxx2 A A A W W xxx3 A A A W W xxx4 A A A W W xxx5 A A A W W xxx6 A A A W W xxx7 A A A W W xxx8 A A A W W xxx9 n Tape and Reel Dimension SOT-25 P W AME AME PIN 1 Carrier Tape, Number of Components Per Reel and Reel Size Package Carrier Width (W) Pitch (P) Part Per Full Reel Reel Size SOT-25 8.0±0.1 mm 4.0±0.1 mm 3000pcs 180±1 mm 9 AME, Inc. Low Power DC/DC Boost Converter AME5131 n Package Dimension SOT-25 Top View Side View SYMBOLS D L MIN E H MILLIMETERS θ1 S1 1.20REF A A 10 0.0472REF 0.15 0.0000 0.0059 b 0.30 0.55 0.0118 0.0217 D 2.70 3.10 0.1063 0.1220 E 1.40 1.80 0.0551 0.0709 1.90 BSC e θ1 A1 b MAX 0.00 2.60 S1 0.07480 BSC 3.00 0.37BSC L Front View MIN A1 H e MAX INCHES 0 o 10 0.95BSC 0.10236 0.11811 0.0146BSC o 0 o 10 0.0374BSC o www.ame.com.tw E-Mail: [email protected] Life Support Policy: These products of AME, Inc. are not authorized for use as critical components in life-support devices or systems, without the express written approval of the president of AME, Inc. AME, Inc. reserves the right to make changes in the circuitry and specifications of its devices and advises its customers to obtain the latest version of relevant information. AME, Inc. , July 2006 Document: 1115-DS5131-A.01 Corporate Headquarter U.S.A.(Subsidiary) AME, Inc. Analog Microelectronics, Inc. 2F, 302 Rui-Guang Road, Nei-Hu District Taipei 114, Taiwan, R.O.C. Tel: 886 2 2627-8687 Fax: 886 2 2659-2989 3100 De La Cruz Blvd., Suite 201 Santa Clara, CA. 95054-2046 Tel : (408) 988-2388 Fax: (408) 988-2489